Patrick p



(No Model.)

P. F. DUNDON.

STEAM BOILER. No. 391,359. Patented Oct. 16, 1888.

n PETERS, Mmmwpbn. wuhin lm. EC.

iINrrEn STATES VATENT OFFICE.

PATRICK F. DUNDON, OF SAN FRANCISCO, CALIFORNIA.

STEAM-BOILER.

SPECIFICATION forming part of Letters Patent No. 391,359, dated October 16, 1888.

Application filed March 26, 1887.

.To all whom, it may concern.-

Be it known that I, PATRICK F. DUNDON, of the city and county of San Francisco, State of California, haveinvented certain new and use ful Improvements in Steam-Boilers; and I do hereby declare the following to be a full, clear, and exact description of the same, reference being had to the accompanying drawings, forming part of the same, in which- Figure 1 represents a perspective view of a return tubular boiler, showing the application of my invention. Fig. 2 is a longitudinal sectional view of the same. Fig. 3 is a transverse sectional view showing the side passages.

My invention relates to certain improve ments in steam-boilers; and it consists in the construction and combination of devices which I shall hereinafter fully describe and claim.

To enable others skilled in the art to make and use my invention, I will now describe its construction and indicate the Inannerin which the same is carried out.

In a former patent, reissued to me August 17, 1886, No. 10,758, I have shown a boiler composed of two separate and independent shells, one constituting or containing the furnace and the other containing the lines to return the heat to the front, and in connec tion with these two separate shells, flues, and furnaces I employ return passages upon the sides.

In my present invention I employ a single boiler-shell, A, having an internal furnace or fire-box, c, surrounded by water in the usual manner, and a main flue or passage, 6, through which all the heat is first carried as it passes to a combustion-ehambcr, f, at the rear of the tubesf. A casing orjacket,l3,surrounds the boiler-shell, and is connected to it at the sides by an internal partition, 0, which divides the jacket into an upper and a lower compartment. In applying the jacket to the returnflue boiler shown, the jacket will preferably be extended entirely around the boiler, and the partition will be extended from the front of the smoke-box B inside to the head of the boiler above the return-fines and along both sides of the boiler. In this case the partition 0 will terminate a short distance from the back end on both sides, and the outlet to the stack will be formed at the front end above the smoke-box, so that the hot gases and products of combustion are passed, first, through the main flue e to the adjacent combustion- Serial No. 282,565. (No model.)

chamberf, thence through the internal tubes,

f, to the furnace end, passing thence into the lower compartment formed by the partition 0. The products of combustion now pass along the lower compartment until they reach the open space D formed by the ends of the partition and the jacket, through which space they pass to the upper compartment, and are finally led along said compartment and directed to the base or outlet of the stack.

I am aware that boilers have been constructed with exterior chamber or fines for the return of the products of combustion, and also that a boiler has been inclosed in two semi'annular chambers for the purpose of superheating the steam. I therefore do not broadly claim such a construction as my invention.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. Aboiler having a furnace at one end and a combustionchamber at the opposite end, flues or tubes extending through the boiler from the combustion-chainher, to the smoke-box, .in combination with chambers or compartments extending along the exterior of the lower sides of the boiler to the furnace end, forming an extension of the smokebox, through which the products of combustion pass, and a second chamber or compartment with which the first one communicates, said second compartment extending over the top of the boiler to the smoke-stack and separated from the lower compartment, substantially as described.

2. The horizontal tubular boiler, having a jacket connecting with the smokebox at the furnace end of the boiler, and a secondjaekct extending over the top of the boiler and connected with the stack at one end and with the lowerjacket at the other end, in combination with the partition between the upper and lowerjackets, and having spaces or openings at the ends, whereby communication is made between the smoke-box and the lowerjacket at one end and the lower and upper jacket at the opposite end of the boiler, substantially as described.

In witness whereof I have hereunto set my hand.

' PATK. F. DUNDON.

\Vitnesses:

S. H. NOURSE, H. 0. LEE. 

